The invention relates to fluid flow meters and more particularly to portable flow meters that can be used to determine the volume of fluid passing through an opening with unknown dimensions, such as the discharge opening which leads to the siphon of an installed toilet bowl.
As a result of increasing conservational awareness and rising water costs, the efficiency of toilets has become of greater concern in recent years. This has resulted in various water saving innovations, such as the development of low flow toilets which use a reduced volume of water with each flush. Municipalities and publicly owned water authorities often provide subsidies for landlords and other building owners to replace inefficient high flush volume toilets with low flow toilets. Nonetheless, to date it has been inconvenient to accurately measure the flush volume of existing toilets installed in a building or other site in order to determine whether it was feasible (from the perspectives of the landlord or owner and the subsidizing authority) to replace the existing toilets with low flow toilets. It has also been difficult to accurately determine the flush volume of new toilets.
In the past, in order to determine the flush volume of an installed toilet it has generally been necessary to disconnect the water supply line going to the toilet and install an inline flow meter in the supply line. This procedure is quite time consuming, with the result that only a relatively small number of toilets could be tested during a water consumption audit of a building or site. Furthermore, as the supply line for flush valve toilets commonly found in commercial buildings are typically located behind finished walls and therefor difficult to access (when compared to flush tank toilets), measurement of the flush volume of installed flush valve toilets has heretofore been impractical with conventional measuring devices.
In the past, various flow meter designs have been proposed for a range of purposes. For example, U.S. Pat. No. 4,700,579 issued Oct. 20, 1987 to Hall discloses a digital flow meter for mounting in a flow delivery line. The meter housing is threaded at opposite ends for coupling to the delivery line. U.S. Pat. No. 3,053,087 issued Sep. 11, 1962 to Waugh also discloses a flow meter threaded at opposite ends for connection to a flow delivery line. Both these flow meters require that the flow delivery line be broken in order for the flow meter to be used, which is inconvenient and time consuming when several tests must be taken at different locations.
It is therefore desirable to provide a portable flow meter which can be efficiently used to measure the flush volume of a toilet by measuring the volume of water passing through the siphon of the toilet. It is also desirable to provide a portable flow meter that can be efficiently used to measure the volume of fluid passing through an opening of unknown diameter.